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Stem cells what they are and their values-converted

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<strong>Stem</strong> <strong>cells</strong>: <strong>what</strong> <strong>they</strong> <strong>are</strong> <strong>and</strong> <strong>their</strong> <strong>values</strong>?<br />

<strong>Stem</strong> cell is the type of cell of the body which is the youngest <strong>and</strong> undifferentiated cell. It has the ability<br />

to differentiate into any kind of cell of the human body. <strong>Stem</strong> <strong>cells</strong> can divide further into more daughter<br />

<strong>cells</strong> under proper conditions. The daughter <strong>cells</strong> have the property of self-renewal to become new stem<br />

<strong>cells</strong> <strong>and</strong> can regrow into specialized <strong>cells</strong> having a specific function as for example blood <strong>cells</strong>, heart<br />

muscle <strong>cells</strong>, brain <strong>cells</strong>, etc.<br />

Types of stem <strong>cells</strong><br />

<strong>Stem</strong> <strong>cells</strong> can be divided on the basis of two categories – source <strong>and</strong> potency.<br />

According to the source, the stem <strong>cells</strong> can be divided into 3 types of stem <strong>cells</strong> – embryonic stem <strong>cells</strong>,<br />

fetal stem <strong>cells</strong> <strong>and</strong> adult stem <strong>cells</strong>.<br />

1. Embryonic stem <strong>cells</strong> – The name itself suggests that these stem <strong>cells</strong> <strong>are</strong> obtained from<br />

embryos. These stem <strong>cells</strong> <strong>are</strong> the inner mass <strong>cells</strong> of the blastocyst. Embryonic stem <strong>cells</strong> <strong>are</strong><br />

pluripotent <strong>and</strong> can develop into any type of cell in the embryo. This potential of stem <strong>cells</strong> gives<br />

rise to the development of more <strong>cells</strong> to the embryo which then grows into a baby.<br />

2. Adult stem <strong>cells</strong> – Adult stem <strong>cells</strong> <strong>are</strong> the undifferentiated <strong>cells</strong> that <strong>are</strong> found in a human<br />

body <strong>and</strong> have the ability to replace the damaged <strong>cells</strong> <strong>and</strong> regenerate the tissues. These stem<br />

<strong>cells</strong> <strong>are</strong> also known as somatic stem <strong>cells</strong> <strong>and</strong> <strong>are</strong> found in children as well as human adults.<br />

These stem <strong>cells</strong> can be isolated from the adults <strong>and</strong> can be grown in laboratory so that <strong>they</strong> can<br />

be used for stem cell therapy of the patient. The adult stem <strong>cells</strong> can be extracted from any part<br />

of the body but the bone marrow contains huge amount of stem <strong>cells</strong><br />

However, extraction of bone marrow is very painful, so researchers have found that stem <strong>cells</strong><br />

can also be extracted from umbilical cord blood <strong>and</strong> tissue which is the richest source of stem<br />

<strong>cells</strong><br />

3. Foetal stem <strong>cells</strong> – Cells derived from a Foetus that retains the ability to divide, proliferate <strong>and</strong><br />

provide progenitor <strong>cells</strong> that can differentiate into specialized <strong>cells</strong>. The embryo is referred to as<br />

a foetus after the eighth week of development. Once a foetal stem cell has been harvested, it<br />

has the potential to live indefinitely in the laboratory. Foetal stem <strong>cells</strong> can be isolated from<br />

foetal blood <strong>and</strong> bone marrow as well as from other foetal tissues, including liver <strong>and</strong> kidney.<br />

Cell potency is the ability of the <strong>cells</strong> to differentiate into other types of <strong>cells</strong>. Greater the potency of the<br />

cell more is the ability of a cell to differentiate into different cell types. According to potency, <strong>cells</strong> can<br />

be divided into 5 types.<br />

1. Totipotent


• Totipotent stem <strong>cells</strong> <strong>are</strong> the most powerful stem cell<br />

• They can differentiate into embryonic <strong>cells</strong> <strong>and</strong> tissues<br />

• Have the ability to develop into a living organism<br />

• e.g. fertilized egg<br />

2. Pluripotent<br />

• These stem <strong>cells</strong> <strong>are</strong> having the ability to renew itself<br />

• They can differentiate into 3 germ layers – ectoderm, endoderm <strong>and</strong> mesoderm<br />

• Also, can develop into any kind of tissues or organs<br />

• e.g. embryonic stem <strong>cells</strong><br />

3. Multipotent<br />

• Multipotent stem <strong>cells</strong> possess the ability of self-renewing<br />

• They can different into a specific kind of cell<br />

• e.g. mesenchymal stem <strong>cells</strong><br />

4. Oligopotent<br />

• Oligopotent stem <strong>cells</strong> have the self-renewing capability<br />

• Restricted to differentiate into closely related cell types<br />

• e.g. hematopoietic stem cell


5. Unipotent<br />

• This stem cell is the least effective<br />

• Have the power to differentiate only into a particular cell type.<br />

• e.g. muscle stem <strong>cells</strong><br />

Benefits of stem <strong>cells</strong><br />

You may be wondering that despite so many other treatments <strong>what</strong> <strong>are</strong> the umbilical cord stem cell<br />

benefits. Overall, the general benefits include minimal risk, minimal recovery time <strong>and</strong> minimum<br />

concern because stem cell therapy uses biological material (cord blood stem <strong>cells</strong>) obtained directly<br />

from the newborn baby. Here <strong>are</strong> five more specific advantages.<br />

• Collection – Collection of cord blood from the umbilical cord is painless <strong>and</strong> risk-free method.<br />

The cord blood is then processed <strong>and</strong> the stem <strong>cells</strong> <strong>are</strong> harvested in the laboratory.<br />

• Outcomes of transplantation – During transplantation of cord blood stem <strong>cells</strong>, there is less<br />

chance of rejection <strong>and</strong> the body of the recipient accepts it easily.<br />

• Differentiative property – As the cord blood stem <strong>cells</strong> <strong>are</strong> young <strong>and</strong> undifferentiated so <strong>they</strong><br />

have the potential to regenerate themselves into any type of <strong>cells</strong> of the body.<br />

• Storage – cord blood stem <strong>cells</strong> can be stored for lifetime in a maintained temperature (-190°C)<br />

<strong>and</strong> in a particular freezer containing liquid nitrogen.<br />

• Infection – When infused into the body of patient cord blood stem <strong>cells</strong> possess less chances of<br />

having any type infection.<br />

“<strong>Stem</strong> <strong>cells</strong> can be extracted from both cord blood <strong>and</strong> cord tissue.”


Cord blood<br />

Cord blood (umbilical cord blood) is blood that remains in the placenta <strong>and</strong> in the attached umbilical<br />

cord after childbirth.<br />

Cord blood is made up of these components - Red blood <strong>cells</strong>, Blood, Plasma, platelets, which <strong>are</strong> found<br />

in the whole blood. In comparison with the whole blood, there <strong>are</strong> some differences in the cord blood,<br />

such as the cord blood contains more natural killer <strong>cells</strong>, lower absolute numbers of the T-<strong>cells</strong> <strong>and</strong> a<br />

higher immature T-<strong>cells</strong> <strong>are</strong> available. However, it is mainly the observation that cord blood contains<br />

various types of stem <strong>and</strong> progenitor <strong>cells</strong>, mostly hematopoietic stem <strong>cells</strong>, that contributes to the<br />

interest of cord blood. Many non-hematopoietic stem cell types <strong>are</strong> also present in cord blood, such as<br />

Mesenchymal stem <strong>cells</strong>, but in a lesser amount than bone marrow. Cord blood can also include<br />

endothelial progenitor <strong>cells</strong> <strong>and</strong> multipotent adult stem <strong>cells</strong>. Cord blood stem <strong>cells</strong> <strong>are</strong> frequently<br />

confused with embryonic stem <strong>cells</strong>. Cord blood stem <strong>cells</strong> <strong>are</strong> the type of adult stem <strong>cells</strong> which is<br />

different from the embryonic stem <strong>cells</strong>.<br />

• Use of cord blood<br />

Cord blood is used the same way that hematopoietic stem cell transplantation is used to<br />

reconstitute bone marrow following radiation treatment for various blood cancers, <strong>and</strong> for<br />

various forms of anaemia. Its efficacy is similar as well.<br />

• Diseases treated by cord blood stem <strong>cells</strong><br />

Cord blood is rich in hematopoietic stem <strong>cells</strong> those <strong>are</strong> pluripotent that means <strong>they</strong> have the<br />

potency to regenerate themselves into any kind of cell of the body. The hematopoietic stem<br />

<strong>cells</strong> can treat diseases related to blood <strong>and</strong> immune system such as leukaemia, anemia, SCIDs,<br />

hypoplasia, etc.


Cord lining<br />

The outermost layer of the umbilical cord is known as cord lining, umbilical cord lining <strong>and</strong> cord tissue.<br />

The umbilical cord itself is an extended part of the placenta <strong>and</strong> is a prolongation of the amniotic<br />

membrane which covers the placenta. The cord tissue membrane is made up of the amniotic layer<br />

which the epithelial layer <strong>and</strong> the sub-amniotic layer which is the epithelial layer. Umbilical cord tissue is<br />

the rich source of two types of stem <strong>cells</strong>, the epithelial stem <strong>cells</strong> <strong>and</strong> the mesenchymal stem <strong>cells</strong>.<br />

• Use of cord lining<br />

Mesenchymal stem <strong>cells</strong> have enormous potential to heal <strong>and</strong> cure different diseases in<br />

damaged tissues <strong>and</strong> organs. EpSC forms the soft tissue that binds, protects <strong>and</strong> covers the<br />

cornea, skin <strong>and</strong> liver of other body structures <strong>and</strong> organs. MSCs <strong>are</strong> the building blocks of bonecartilage,<br />

muscle, fibrous tissues <strong>and</strong> fat tissues in our body.<br />

• Diseases treated by stem <strong>cells</strong> harvested from cord lining<br />

The cord lining also contains stem <strong>cells</strong> as it is the rich source of mesenchymal stem <strong>cells</strong> (MSCs)<br />

<strong>and</strong> epithelial stem <strong>cells</strong> (EpSCs). These mesenchymal stem <strong>cells</strong> can help in treating diseases<br />

such as autism, multiple sclerosis, spinal cord injury <strong>and</strong> epithelial stem <strong>cells</strong> help in treating<br />

diseases related to skin, the cornea of the eye, etc.<br />

Cord blood collection method <strong>and</strong> storage<br />

Once your baby is born <strong>and</strong> separated, the umbilical cord is clamped <strong>and</strong> then the cord blood is<br />

collected in a single-use sterile 250mL blood bag. This cord blood along with cord tissue <strong>and</strong> mother’s<br />

blood sample is then kept in the Kit box which is transported to the storage laboratory by maintaining a<br />

controlled temperature. In the laboratory, the cord blood is processed by an advanced automated<br />

technology known as AXP®II for harvesting hematopoietic stem <strong>cells</strong>. These stem <strong>cells</strong> <strong>are</strong> then stored in<br />

compartmentalized cryopouches at -190°C in liquid nitrogen. This complete method of collection,<br />

processing <strong>and</strong> storage is known as cord blood banking.


Reasons for choosing cord blood stem <strong>cells</strong> for treatment<br />

Children with blood-related disorders such as leukemia <strong>and</strong> inherited blood diseases like Fanconi's<br />

anemia <strong>are</strong> used for the treatment of cord blood. The patient who is suffering from these types of<br />

diseases is first provided with chemotherapy to destroy the damaged <strong>and</strong> diseased <strong>cells</strong> of the body.<br />

Then the young <strong>and</strong> undifferentiated stem <strong>cells</strong> <strong>are</strong> infused into the body of the patient. These stem<br />

<strong>cells</strong> can treat diseases by regenerating themselves into daughter stem <strong>cells</strong> which further replace the<br />

damaged <strong>cells</strong> of the body to repair the tissues <strong>and</strong> organs.<br />

Therefore, cord blood provides a beneficial option for patients when comp<strong>are</strong>d to bone marrow<br />

transplants. The process of collection of cord blood is easier than bone marrow <strong>and</strong> can be stored when<br />

frozen. The risk of immune failure <strong>and</strong> infections, including Graft <strong>and</strong> Host Disease, often seems less<br />

than bone marrow. This means that cord blood does not need to be as perfectly matched to the patient<br />

as bone marrow.<br />

Nevertheless, there <strong>are</strong> also restrictions on cord blood transplants. Cord blood c<strong>are</strong> for adults usually<br />

requires two cord blood units for treatment. Clinical studies using adult dual cord blood transplantation<br />

have shown similar results to other HSC sources, like bone marrow or peripheral blood mobilized. There<br />

<strong>are</strong> currently experiments to extend a single blood cord for adult use.

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